1. Field of the Invention
Embodiments of the present invention relate to encoding and/or decoding of image data, and more particularly, to a system, medium, and method encoding and/or decoding image data using adaptive quantization based on the number of bits per pixel in an input image.
2. Description of the Related Art
An image acquired by a camera may be displayed with an appropriate size, e.g., with a number of pixels, through sampling. When the image is displayed, the number of bits required to represent the value of each pixel is determined. Here, to display the image with high image quality, there has been a requirement to increase of the number of representable values, thereby increasing the number of bits per pixel. The number of bits has gradually increased also due to the advancing development of image devices. For example, although 8 bits have been used in many fields, recently, 10 or 12 bits have been used in application fields where high quality images are desired.
For conventional image compression, compression schemes for 8-bit images have been generally developed. For example, VC-1 (VC-1 Compressed Video Bitstream Format and Decoding Process), corresponding to a compression video codec standardized by the Society of Motion Picture and Television Engineers (SMPTE), provides effective quantization schemes suitable for every case using various kinds of image information. However, in the conventional quantization schemes used in VC-1, the number of bits per pixel is fixed to 8 bits per pixel. Although an 8-bit image is popularly used for image coding schemes, the image quality of the 8-bit image is limited. Thus, considering the gradual increase in the demand for images having higher image quality, the present inventors have found that it is desirable to provide a quantization scheme suitable even for a images having more than 8 bits per pixel.